Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cellular lipid patterns of seven strains of microorganisms were examined by gas-liquid chromatography in this preliminary study. The chloroform methanol-soluble lipids were extracted by the Soxhlet method from dried cultures which had been grown at 25 +/- 2 C for 18 hr with mechanical shaking. The cellular extract was methylated by use of a low temperature sulfuric acid method, and the resulting methyl esters were chromatographed. Considerable differences in the lipid patterns among the seven microorganisms tested indicated that this method might be useful for the identification of closely related microbial genera, and possibly for species differentiation.
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PMID:Lipid patterns of selected microorganisms as determined by gas-liquid chromatography. 486 May 30

1. The actions of rimiterol [erythro(3,4-dihydroxyphenyl, 2-piperidyl methanol hydrobromide)], a new sympathomimetic bronchodilator, have been compared with those of salbutamol and laevoisoprenaline on the heart and lungs, and on contractions of the soleus muscle of cats under chloralose anaesthesia.2. Rimiterol and salbutamol injected intravenously were about equipotent in all tests, and were about 8 times less potent than laevoisoprenaline both in opposing the bronchoconstrictor action of 5-hydroxytryptamine, and in decreasing the tension and degree of fusion of incomplete tetanic contractions of the cat soleus muscle. They were about 19 times less potent than laevoisoprenaline in increasing heart rate.3. The effect on the soleus muscle is considered to be analogous to the muscle tremor that often occurs in man, and the results therefore suggest that systemic administration of bronchodilator doses of rimiterol, like salbutamol, may produce muscle tremor as an unwanted side-effect.4. When equipotent doses to oppose 5-hydroxytryptamine-induced bronchospasm were compared, rimiterol and salbutamol produced less tachycardia than did laevoisoprenaline. In order to match the tachycardia produced by laevoisoprenaline, the doses of rimiterol or salbutamol had to be increased about two and a half times. This safety margin for salbutamol in the cat is considerably less than that reported by others for different species, which suggests that beta(1)- and beta(2)-adrenoceptors may be less clearly differentiated in the cat than they are in other laboratory animals.
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PMID:Actions of the sympathomimetic bronchodilator, rimiterol (R798), on the cardiovascular, respiratory and skeletal muscle systems of the anaesthetized cat. 508 31

Organic materials were extracted from airborne particles by shaking with different solvent systems including acetone, benzene, cyclohexane, dichloromethane (DCM), methanol, a mixture of acetone and DCM and a combination of benzene, cyclohexane and methanol. The solvent-extracted materials were tested for mutagenic activity with the Ames Salmonella/microsomal assay system. Acetone- and cyclohexane-extracted materials gave the highest and lowest mutagenic activities, respectively. Re-extraction experiments confirmed that most of the mutagenic material from air particles cannot be extracted by cyclohexane. The sequential extraction with acetone followed by DCM gave a better mutagenic response than acetone alone or acetone in combination with DCM. Extraction with varying amounts of solvent indicated that 1 ml of acetone per mg of airborne particles reached the maximum recovery of mutagenic material.
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PMID:Mutagenicity studies of ambient airborne particles. I. Comparison of solvent systems. 635 84

Modifications to a published method are described for the determination of deoxynivalenol (DON) in wheat by gas chromatography with electron capture quantitation of the heptafluorobutyrate derivative. In the modified method, DON is extracted by shaking the sample with methanol-water on a wrist-action shaker, followed by filtration through rapid flow paper. One concentration step is eliminated, and a hexane wash is incorporated to remove toluene from the silica gel column. Recoveries of DON from wheat samples spiked at 0.1, 0.5, and 1.0 ppm ranged from 77.3 to 86.3% and averaged 81.5%.
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PMID:Gas chromatographic determination of deoxynivalenol in wheat. 664 61

The use of partition coefficients Poct obtained from an n-octanol-water partitioning system has become a standard method for modelling biological membranes and thereby quantifying the hydrophobicity of a given compound as log Poct = log Coct--log Cwater. However, there is no convenient method available to determine the log Poct value accurately. The conventional flask-shaking method is a laborious and time consuming procedure, often complicated by instability in aqueous media, impurities and the tendency for the compound to dissociate. There have been recently attempts using HPLC to determine the hydrophobicity of organic compound. The retention behaviour of about fifty organic compounds in HPLC systems have been examined. Using methanol-water as the mobile phase, a linear relationship between the volume fraction of organic modifier and the logarithm of the capacity factor (log K') over limited range was obtained for standards. However, unfortunately, the correlation between log Kw obtained from the extrapolated K' values with pure water as eluent and log Poct values was not good (r = 0.83). Using this octadecylsilyl column with the mobile phase (methanol: water = 70:30), standards fall on the three straight lines with good correlations (r = 0.99) between the log Poct and log K' values.: one for benzenes and aliphatic compounds, the second for phenols, anilines and hydrogenacceptor benzene derivatives and the third for benzoic acids, respectively. The PHPLC values of methacrylates, initiators and miscellaneous compounds which are widely in dentistry were determined using these three regression lines.
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PMID:[Determination of hydrophobic parameters (log PHPLC) for methacrylates, initiators and miscellaneous compounds used in dentistry by high-performance liquid chromatography (HPLC) (author's transl)]. 694 95

4-Hydroxy-3-nitrobenzenearsonic acid (roxarsone) is administered in animal feed as a growth stimulant over a concentration range of 25-50 ppm. The drug is extracted from 5 g feed with 200 mL aqueous 1.0% ammonium carbonate solution and 5 min of mechanical shaking. Undissolved feed particles are allowed to settle and 1.0 mL aliquot of extract is diluted with 9.0 mL 15% methanol solution. This solution is subjected to sample atomization by a graphite furnace and arsenic detection by atomic absorption spectrophotometry (AAS). Roxarsone recovery from nonmedicated commercial feed fortified at 25 ppm was 103.6% with a relative standard deviation (RSD) of 4.0%. Recovery for 50 ppm fortification was 104.5% (RSD 4.3%). Roxarsone assay results by furnace AAS were compared with results by the current AOAC spectrophotometric method and the AOAC total arsenic method. Results by the 3 methods compare well. The procedure was also used to determine other organic arsenicals and inorganic arsenic in laboratory-fortified feed samples; these recoveries were essentially theoretical.
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PMID:Graphite furnace atomic absorption spectrophotometric determination of 4-hydroxy-3-nitrobenzenearsonic acid, other organic arsenicals, and inorganic arsenic in finished animal feed. 709 54

Sulfonamide drugs are extracted from feed and feed premixes by shaking with 0.15N HCl in 25% methanol. The extract is diluted, clarified, and chromatographed on a reverse phase C18 column. Mobile phases used are methanol-2% acetic acid (35 + 65) and acetonitrile-2% acetic acid (18 + 82) for sulfamethazine (SMT) and sulfathiazole (STZ), respectively. A solution of dimethylaminobenzaldehyde (DMAB) is added to the column eluate and the resulting sulfonamide-DMAB complex is detected at 450 nm. The method was tested for linearity, recovery, and precision across a broad sample range. Recovery was 100.6 +/- 2.3% and 96.3 +/- 1.6% for STZ and SMT, respectively. Linearity was excellent (r2 = 0.9985 for STZ and r2 = 0.9996 for SMT) as was within-day precision (RSD = 2.00% for STZ and 1.52% for SMT). The method was compared with the Bratton-Marshall colorimetric method. Analysis of 14 STZ and 15 SMT samples failed to detect any bias between the 2 methods. Some practical aspects of the use of this technique are discussed.
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PMID:Use of post-column derivatization in liquid chromatographic determination of sulfamethazine and sulfathiazole in feeds and feed premixes. 711 88

Several techniques were evaluated for extracting triphenyl phosphate (TPP), 14C-labeled TPP, cresyl diphenyl phosphate, and tricresyl phosphate isomers (o-TCP, m-TCP, and p-TCP) from fish and sediment samples. Extracts of fish samples were cleaned up by gel permeation chromatography/alumina column chromatography; sediment extracts received alumina treatment only. Compounds were determined by gas-liquid chromatography (GLC) with nitrogen-phosphorus detection. Methanol/Polytron and hexane/ball mill extraction of fish samples fortified at 0.01, 0.1, and 1.0 microgram/g levels gave overall recoveries of the 5 compounds of 89 and 97%, respectively. Methanol recovered more radioactivity (97%) from fish exposed to 14C-TPP in aquaria for 24 h than did hexane from fish exposed for 16 h (79%). Refluxing fortified sediment (0.05 and 0.5 microgram/g) with methanol-water (9 + 1) gave significantly higher recoveries (88%) of the 5 triaryl phosphates than did dichloromethane-methanol (1 + 1) reflux or acetone-hexane (1 + 1) Soxhlet extraction. Recoveries of TPP and o-, m- and p-TCP from fortified river water (0.5, 5.0, and 50 microgram/L) by shaking with dichloromethane ranged from 91 to 118%. Some problems were encountered with interfering GLC peaks at low (microgram/g) levels in fish and sediment extracts despite the use of nitrogen-phosphorus specific detectors.
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PMID:Extraction and cleanup of fish, sediment, and water for determination of triaryl phosphates by gas-liquid chromatography. 720 13

We report 2 survivors of severe methanol poisoning who developed, apart from blindness, a Parkinson-like extrapyramidal syndrome characterized by reduced initiative, poor voice volume, masked facies, mild tremor, rigidity, and bradykinesia. Both patients were mildly demented and 1 had hyperreflexia and bilateral Babinski responses. Computed tomographic scans in both patients demonstrated bilateral symmetrical infarction of the frontocentral white matter and putamen. Electromyography in 1 patient showed extensive denervation, mainly involving the legs, but normal motor conduction velocities. L-Dopa administered to the more severely affected patient had no effect on the parkinsonian features. Autopsy revealed cystic resorption of the putamen and the frontocentral subcortical white matter in additon to widespread neuronal damage throughout the cerebrum, cerebellum, brainstem, and spinal cord.
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PMID:Methanol poisoning: a clinical and pathological study. 742 69

A direct competitive enzyme-linked immunosorbent assay (ELISA) screening method for zearalenone in corn, wheat, and feed at 500 ng/g was evaluated by 23 collaborators (22 laboratories) in an international collaborative study. Eighteen samples of spiked or naturally contaminated corn, wheat, and pig feed were prepared by the sponsoring laboratory and sent for testing with complete test kits to participating collaborators in Canada, Italy, Sweden, The Netherlands, and the United States. Test samples were extracted with methanol-water solution (70 + 30) by shaking on a wrist-action shaker for 3 min. A portion of the extract was mixed with an equal volume of zearalenone-enzyme conjugate, and the mixture was incubated with zearalenone-specific monoclonal antibodies coated onto microtiter wells. All test samples were assayed in duplicate. One of 52 (2%) blanks was reported positive. Thirty-nine of the 52 (75%) samples that were spiked at 500 ng/g were reported as positive. Forty-nine of the 51 (96%) samples with concentrations at or above 1000 ng/g were reported as positive. The overall incidence of false negatives was 6.0% and the incidence of false positives was 22.7% by the ELISA method. Only one (3.4%) false negative was reported for samples containing > or = 800 ng/g. In the spectrophotometric method, 8 collaborators determined approximate levels of zearalenone in test samples from standard curves constructed from spiked extracts (0-3000 ng/g of each commodity tested). This method gave and overall incidence of false negatives of 5.7% and false positives of 17.8%. Average relative standard deviations, RSDr (repeatability) and RSDR (reproducibility), were 11.6 and 25.1% for spiked samples and 11.7 and 33.1% for naturally contaminated samples, respectively. Standard curves were constructed with each set of samples assayed. Comparison of absorbance values from these standard curves indicate the performance of reagents and antibody used in the assay. The ELISA method has been adopted first action by AOAC INTERNATIONAL as a screening method for zearalenone at > or = 800 ng/g in corn, wheat, and pig feed.
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PMID:Enzyme-linked immunosorbent assay for detection of zearalenone in corn, wheat, and pig feed: collaborative study. 781 59


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